CN114810818A

CN114810818A - Rolling bearing with cage guide flange

Info

Publication number: CN114810818A
Application number: CN202210100597.1A
Authority: CN
Inventors: 布鲁诺·卡波尔迪; 文森特·布雷多; 赫维·东丹
Original assignee: SKF AB
Current assignee: SKF AB
Priority date: 2021-01-29
Filing date: 2022-01-27
Publication date: 2022-07-29
Also published as: US20220243763A1; DE102021102133A1; US11754122B2

Abstract

A bearing comprises a first ring (10), a second ring (12) and at least one row of radial and axial rolling bodies (22, 18) arranged between axial and radial raceways (36, 34, 28, 26) of the first and second rings (10, 12). The second ring (12) comprises a protruding nose (40) engaged in an annular recess (38) of the first ring (10), the nose (40) being provided with an axial raceway (34) and a radial raceway (26) of the second ring (12). The bearing further comprises at least one cage (42) for holding the rows of axial rolling elements (18) and at least one flange (44) for guiding and holding the cage (42) in the radial direction. The flange (44) axially abuts against a flat surface (12 d) of the second ring (12) ₁ ). The bearingA plurality of set screws (50) are also included to secure the flange (44) to the second ring (12), the set screws (50) extending axially through the flange (44).

Description

Rolling bearing with cage guide flange

Technical Field

The invention relates to the field of rolling bearings.

The invention relates in particular to the field of large-diameter rolling bearings having an inner ring and an outer ring arranged concentrically about an axis of rotation running axially.

Such large-diameter rolling bearings can be used, for example, in tunnel boring machines, mining machines or wind turbines.

Background

A large diameter rolling bearing comprises two concentric inner and outer rings, and at least two rows of axial and radial rollers disposed between the inner and outer rings. The axial and radial rows of rollers are arranged between a nose (nose) formed in the inner or outer ring, designated as the "nose ring", and a recess (/ groove) (groovee) formed in the other of the inner or outer ring. The rolling bearing further comprises at least one cage for retaining the axial rows of rollers. Reference may be made, for example, to EP-B1-2851575.

In a specific design, a flange (flange) of the guiding cage is fixed to the outer or inner ring defining the recess. If the inner ring forms (/ defines) said recess, said flange is mounted in radial contact against the outer cylindrical surface of the (contact against) inner ring. Alternatively, if the recess is formed by the outer ring, the flange is radially mounted in contact against the cylindrical bore of the outer ring.

A plurality of set screws are used to secure the flange to the inner race or the outer race. The screws are circumferentially spaced (/ circumferentially spaced). Each screw extends radially through the flange and engages in a threaded hole formed in the outer cylindrical surface of the inner race (or in the cylindrical inner bore of the outer race).

In either case, some of the set screws may break at the cylindrical interface between the flange and the inner or outer ring when the rolling is affected by vibrations during operation. Broken portions of the screw may fall into the drive system (gearing system) of the associated machine, causing significant losses.

Disclosure of Invention

It is an object of the present invention to overcome this drawback.

The invention relates to a rolling bearing comprising a first ring, a second ring, at least one row of radial rolling elements arranged between axial raceways of the first and second ring, and at least one row of axial rolling elements arranged between radial raceways of the first and second ring.

The term "axial rolling element" is understood to mean a rolling element suitable for carrying an (acomod) axial load. The term "radial rolling element" is understood to mean a rolling element suitable for carrying radial loads.

The second turn comprises a protruding nose (/ head) (nose) fitting (engaged) in the annular recess (groove) of the first turn. The nose portion is provided with the axial raceway and the radial raceway of the second ring.

The rolling bearing further comprises at least one cage for holding the axial rolling bodies of the row. The rolling bearing further comprises at least one flange (flange) for guiding and retaining the cage in the radial direction.

According to a first general feature, the flange bears axially against a flat surface (flat surface) of the second ring.

According to a second general feature, the rolling bearing further comprises a plurality of fixing screws for fixing said flange on the second ring.

According to a third general feature, the set screw passes (/ extends) through (extended through) the flange in the axial direction.

With this design, the risk of screw breakage is greatly reduced, since there is a flat contact surface between the guide flange and the front surface (/ end face) of the second ring (front face). There is no gap between the guide flange and the second ring.

The recess may have disposed therein the axial and radial raceways of the first ring.

Each set screw may be engaged (engaged) in a threaded bore extending axially from the planar surface of the second ring.

Preferably, said flat surface of the second turn extends in a radial direction. Alternatively, the flat surface of the second turn may have other shapes. For example, said flat surface of the second turn may extend obliquely.

In one embodiment, the second ring is provided with a front opposing surface (/ end surface) (front faces) that defines the axial thickness of the second ring in the axial direction. A second ring is formed on one of these front surfaces (/ end faces) in axial abutment against said flat surface of said flange.

The front surface (/ end surface) of the second turn may have a stepped shape, may be provided with a first surface and a second surface offset outwardly in axial direction with respect to the first surface. The second ring is formed by said first surface in axial abutment against said flat surface of said flange.

As an alternative, the front surface (/ end surface) of the second turn may extend in a single radial plane.

In an advantageous embodiment, the flange comprises at least one root, which engages in a groove of the second turn. This limits the shearing effect in the radial direction, thereby improving the life of the bearing.

The root of the flange may have an annular shape. As a further alternative, the flange may comprise a plurality of roots spaced apart (preferably regularly distributed (/ equidistantly distributed)) in the circumferential direction.

The groove may extend axially from the planar surface of the second turn. The groove may have an annular shape.

In another embodiment, the flange may not be provided with the root portion.

Advantageously, the first ring comprises at least one retaining shoulder axially facing at least partially the flange and the set screw, the retaining shoulder being located axially on the opposite side of the second ring from (with regard to) the row of axial rolling bodies.

Said shoulder is capable of retaining and blocking the screws initially fixed to the second ring inside the flange in the event of vibrations acting on the rolling bearing causing these screws to disengage or break.

For this purpose, the axial clearance between the flange and the retaining shoulder of the first ring is preferably smaller than the length of the respective fixing screw which projects axially beyond the flat surface of the second ring, contacting the flange.

Said shoulder of the first ring may have an annular shape. Alternatively, the first ring may include a plurality of circumferentially spaced retaining shoulders, wherein each shoulder faces one of the set screws.

In one embodiment, the first ring may comprise at least one support ring and a retaining ring which are axially stacked (braced) on one another, the radial raceway of the first ring being provided on said support ring. In this case, the retaining shoulder may be provided on the support ring.

In another embodiment, the first ring may not be provided with the shoulder.

In one embodiment, the rolling bearing comprises at least two rows of axial rolling bodies arranged on both axial sides of the nose of the second ring.

In one embodiment, the first ring is an outer ring and the second ring is an inner ring. Alternatively, the first ring may be an inner ring and the second ring may be an outer ring.

Drawings

The following description of the invention is given by way of non-limiting example and illustration. The invention and its advantages will be better understood by studying the detailed description of these embodiments. In the drawings:

fig. 1 is a partial sectional view of a rolling bearing according to a first example of the invention; and

fig. 2 is a detail view of fig. 1.

Detailed Description

The rolling bearing shown in fig. 1 is a large-diameter rolling bearing including a first ring 10 and a second ring 12. In the illustrated example, the first turn 10 is an outer turn and the second turn 12 is an inner turn. In this example, the inner race 12 is a rotating race and the outer race 10 is a non-rotating race. The rolling bearing may be used, for example, in a tunnel boring machine, a wind generator, or any other application using a large diameter rolling bearing.

The outer ring 10 and the inner ring 12 are concentric and extend in the axial direction along a bearing axis of rotation (not shown) running in the axial direction. In the illustrated embodiment, the bearing rings 10, 12 are of the solid (solid) type.

The outer ring 10 is formed as a split ring comprising a first support ring 14 and a second retaining ring 16 stacked axially against each other. Each of the support and retaining rings 14, 16 of the outer race is provided with a plurality of aligned through holes (not shown) for connection by means of adapted bolts.

In the illustrated example, the rolling bearing comprises three rows of

axial rollers

18, 19, 20 arranged between the inner and

outer races

12 and 10 to form an axial thrust (axial thrust) and one row of radial rollers 22 arranged between the inner and outer races to form an axial thrust.

In the illustrated embodiment, the rolling bearing also comprises a thrust ring (thrust ring)24 mounted axially between the axial rollers 20 of the row and the outer ring 10. The thrust ring 24 may be named "spring ring". A thrust ring 24 is interposed axially between the axial rollers 20 of the row and the retaining ring 16 of the outer race. The rolling bearing further comprises a plurality of spring systems (not shown) for pushing the thrust ring 24 in the axial direction against the axial rollers 20. The spring system is mounted on the retaining ring 16 of the outer ring. As a further alternative, the rolling bearing may be provided without such a retaining ring 24 and spring system.

The

rollers

18, 19, 20, 22 of the same row are identical to one another. Each

roller

18, 19, 20, 22 comprises a cylindrical outer rolling surface (/ outer rolling surface). The axis of rotation of each roller 22 is parallel to the axis of the bearing and perpendicular to the axis of each

roller

18, 19, 20. In the illustrated example, the rows of rollers 18 are stacked (superordered) on the rows of rollers 19. Alternatively, the two rows of

rollers

18, 19 may be replaced by a single row of rollers.

The

rollers

18, 19 are disposed axially between annular

radial raceways

26, 28 formed on the inner and

outer races

12 and 10, respectively. A radial raceway 28 is formed on the outer race support ring 14. The

raceways

26, 28 face each other in the axial direction.

The rollers 20 are disposed axially between annular

radial raceways

30, 32 formed on the inner race 12 and thrust ring 24, respectively. The

raceways

30, 32 face each other in the axial direction. The rows of

rollers

18, 19 are axially spaced from the rows of rollers 20.

The rollers 22 are disposed radially between annular

axial raceways

34, 36 formed on the inner and

outer races

12 and 10, respectively. An axial raceway 36 is formed on the outer race support ring 14. The

raceways

34, 36 face each other in the radial direction. The row of rollers 22 is radially offset outwardly (offset outswards) with respect to the row of

rollers

18, 19, 20. The rollers of the row (/ roller row) 22 are axially positioned between the rollers of the

row

18, 19 and 20.

The outer race 10 includes an annular recess (annular groove)38 opening radially inwardly toward the inner race 12. The outer race 10 includes a stepped inner cylindrical surface or bore 10a, thereby forming the annular recess 38.

The inner race 12 includes an annular protruding nose (nose)40 that fits (engages) into an annular recess 38 of the outer race. The nose 40 expands radially outward (extensions). Said nose 40 protrudes radially (radially) from the outer cylindrical surface 12a of the inner ring.

The inner race 12 further includes an inner cylindrical bore (hereinafter also simply referred to as "inner bore") 12b that is diametrically opposed to the outer cylindrical surface 12 a. In the illustrated example, the inner bore 12b of the inner race is provided with gear teeth (not labeled). The inner ring 12 further comprises two opposite radial front surfaces (/ two radially running opposite end surfaces) 12c, 12d defining an outer cylindrical surface 12a and an inner bore 12b in the axial direction. The

front surfaces

12c, 12d define the axial thickness of the inner ring. As will be described later, the front surface 12d has a stepped shape.

The rows of

rollers

18, 19, 20 are disposed axially between the nose 40 of the inner race and the recess 38 of the outer race. The rows of

rollers

18, 19 are arranged on one side of the nose 40 and the rows of rollers 20 are arranged on the other side (of the nose 40).

The radial raceway 26 is located on the nose 40. A first radial flank (flank)40a of the nose defines the radial raceway 26. A second radial flank 40b of the nose, opposite the first radial flank 40a, defines the radial raceway 30. The oppositely disposed first and

second flanks

40a, 40b of the nose portion axially define the nose portion. The radial raceway 28 is located on an outer race recess 38. The radial raceway 32 is located on the thrust ring 24.

The rollers 22 of the row are arranged radially between the nose 40 of the inner ring and the recess 38 of the outer ring. The

axial raceways

34, 36 are located on the nose 40 and the recess 38, respectively. The outer cylindrical surface of the nose 40 defines the axial raceway 34. The axial bottom of the recess 38 defines the axial raceway 36. The axial raceway 36 faces radially the outer cylindrical surface of the nose 40 on which the axial raceway 34 is formed. Said outer cylindrical surface of the nose 40 is radially offset (offset) from the outer cylindrical surface 12a of the inner ring 12. As a result, the axial raceway 34 is also radially offset from the outer cylindrical surface 12 a. The outer cylindrical surface of the nose 40 extends axially between oppositely disposed

radial flanks

40a, 40b of said nose.

In the illustrated example, the inner race 12 is integrally formed. Alternatively, the inner ring 12 may be divided in the axial direction into at least two separate parts (separate parts) fixed together. In another variation, the nose portion 40 may be manufactured separately from (separately from) the inner ring body portion.

As previously mentioned, the outer ring 10 is divided axially into two separate parts: a support ring 14 and a retaining ring 16. The support ring 14 and the retaining ring 16 together define a recess 38.

The rolling bearing further comprises a cage 42 for keeping the

axial rollers

18, 19 spaced apart in the circumferential direction. As described later, the rolling bearing further includes an annular flange (flange)44 for guiding and retaining the cage 42 in the radial direction.

The cage 42 maintains regular (regular) circumferential spacing between the

axial rollers

18, 19. The cage 42 is accommodated in an annular space defined between the inner ring 12 and the outer ring 10 in the axial direction and between the outer ring 10 and the flange 44 in the radial direction. Each

axial roller

18, 19 is held by a cage 42.

The cage 42 defines pockets configured to receive one axial roller 18 and one axial roller 19, respectively. As previously mentioned, in the example illustrated, the rolling bearing comprises two rows of

rollers

18, 19 stacked together. Alternatively, the rolling bearing may comprise only one row of rollers arranged between the

raceways

26, 28. In this case, each pocket of the cage accommodates only one axial roller.

The cage 42 may also be segmented circumferentially and formed from a plurality of successive cage segments. The holder 42 may be made of metal, such as steel, copper, or a plastic material, for example.

Similarly, the rolling bearing further includes cages 46, 48 for holding the rollers 20, 22, respectively, in a circumferentially spaced apart relationship.

As mentioned before, the flange 44 is provided for guiding the cage 42 in the radial direction and also for holding the cage. The flange 44 is fixed to the inner race 12. The flange 44 extends perpendicular to the

raceways

26, 28 of the inner and outer races.

In the illustrated example, the flange 44 is offset radially inward relative to the cage 42. A slight radial clearance (not labeled) is provided between the cage 42 and the flange 44. The cage 42 is mounted around the flange 44. The cage 42 is free to move rotationally relative to the flange 44.

The flange 44 abuts against the front surface 12d of the inner race in the axial direction. As described previously, in the illustrated example, the front surface 12d has a stepped shape. The front surface 12d is provided with a first radial flat surface 12d axially abutted by the flange 44 ₁ And axially opposite to said first surface 12d ₁ Outwardly offset second radial flat surface 12d ₂ . First and second surfaces 12d of the front surface 12d ₁ 、12d ₂ With an axial wall extending therebetween. As a further alternative, it is possible to provide the entire flat front surface 12d of the inner ring, which extends in one single radial plane of the rolling bearing.

The rolling bearing includes a plurality of set screws 50 that secure the flange 44 to the inner race 12. The screws 50 are circumferentially spaced apart, preferably regularly (/ equally). The screw 50 extends axially (axially) through the flange 44.

As shown in the figure2, each screw 50 is engaged in a threaded bore 52 of the inner race 12. Each threaded hole 52 extends from the first flat surface 12d of the front surface 12d of the inner race ₁ Extending in the axial direction. Each screw 50 extends axially within a through hole 54 formed in the flange 44. Accordingly, the flange 44 includes a plurality of circumferentially spaced through holes 54. Each through hole 54 extends in the axial direction. The head of each screw 50 abuts the flange 44 in the axial direction.

The flange 44 is provided with an annular root portion 56, and the root portion 56 is engaged with a first flat surface 12d formed on the front surface 12d of the inner ring ₁ And an annular groove (annular groove) 58. The grooves 58 extend from the first flat surface 12d ₁ Extending axially. The grooves 58 open axially outward. The root 56 radially abuts against a side wall (/ wall) of the groove 58 that radially defines the groove 58 (wall).

The flange 44 includes an outer cylindrical surface 44a, the outer cylindrical surface 44a forming a guide surface that can support (bear) the cage 42. The flange 44 also includes an inner cylindrical bore 44b diametrically opposed to the outer cylindrical surface 44 a. The flange 44 also comprises two opposite radial front surfaces (/ two radially running opposite end surfaces) 44c, 44d which define an outer cylindrical surface 44a and an inner bore 44b in the axial direction. The front faces 44c, 44d define the axial thickness of the outer flange 44.

The front surface 44c of the flange is flat, axially abutting against the first flat surface 12d of the front surface 12d of the inner ring ₁ . The root portion 56 protrudes in the axial direction with respect to the front surface 44c of the flange. The root portion 56 also projects radially outwardly relative to the outer surface 44a of the flange.

Each through hole 54 opens on the front surface 44c and the front surface 44d of the flange. In the illustrated example, each screw 50 is received within a flange 44. Alternatively, the screw 50 may protrude slightly in the axial direction with respect to the front surface 44d of the flange.

The flange 44 has an annular shape. The flange 44 is formed as a sleeve. The flange 44 may be integrally formed. Alternatively, the flange 44 may be circumferentially segmented. The flange 44 may be made of metal, such as steel, copper, or a plastic material, for example.

In the illustrated example, the outer race 10 includes an annular shoulder 60 extending radially inward, axially facing the flange 44 in part. The shoulder 60 continues (extends) the inner bore of the outer race. The support ring 14 of the outer race includes the shoulder 60. Here, the shoulder 60 is formed integrally with the support ring 14.

The shoulder 60 is located axially opposite the inner race 12 relative to the rollers 18. The shoulder 60 faces the front surface 44d of the flange at an axially upper portion. The shoulder 60 partially faces each screw 50 in the axial direction. More precisely, the shoulder 60 faces, in an axially upper portion, the head of each screw 50. Here, a small axial gap 62 is provided between the flange 44 and the shoulder 60.

The shoulder 60 is capable of retaining or blocking one or more screws 50 within the flange 44 in the event that vibrations applied to the rolling bearing cause the screws to disengage or break. In the illustrated example, the axial gap 62 is small, e.g., less than 1 cm. Alternatively, the first flat surface 12d, which is smaller than the screw 50 in the axial direction with respect to the front surface 12d of the inner race, may be kept in the clearance ₁ The length of the projection provides a greater axial clearance.

Furthermore, as previously mentioned, in this example, the first ring of the rolling bearing is the fixed outer ring 10 and the second ring is the rotating inner ring 12.

Alternatively, the reverse arrangement may be provided, with the first ring forming the fixed inner race and the second ring forming the rotating outer race.

In this case, the outer ring is provided with a projecting nose 40 extending radially inwardly. The recess 38 is formed in the inner race and opens radially outward. The nose 40 fits (/ engages) (engaged) in the recess 38. In such an embodiment, the guide flange 44 is fixed to the outer ring. The flange is radially offset outward relative to the cage 42. The flange is fitted around the holder 42. The inner bore of the flange forms a guide surface that supports the retainer 42. The flange, as in the previously described illustrated embodiment, is secured to the outer race. With this opposite arrangement, if the rolling bearing is provided with a retaining shoulder 60, this shoulder is provided on the support ring 14 of the inner ring.

In the example described above, the rolling bearing is provided with four rows of rolling elements. Alternatively, the rolling bearing may comprise only two rows of rolling elements or three rows of rolling elements, or five or more rows of rolling elements. In the illustrated example, the rolling elements are rollers. The rolling bearing may also comprise other types of rolling bodies, for example balls.

Claims

1. Rolling bearing comprising a first ring (10), a second ring (12), at least one row of radial rolling bodies (22) arranged between axial raceways (36, 34) provided on the first and second ring, and at least one row of axial rolling bodies (18) arranged between radial raceways (28, 26) provided on the first and second ring, the second ring (12) comprising a protruding nose (40) engaging in an annular recess (38) of the first ring (10), the nose (40) being provided with the axial raceway (34) and the radial raceway (26) of the second ring (12), the rolling bearing further comprising at least one cage (42) for retaining the at least one row of axial rolling bodies (18) and at least one flange (44) for guiding and retaining the cage (42) in radial direction, characterized in that, the flange (44) axially abuts against a flat surface (12 d) of the second ring (12) ₁ ) The rolling bearing further comprises a plurality of fixing screws (50) for fixing the flange (44) to the second ring (12), the fixing screws (50) extending in an axial direction through the flange (44).

2. Rolling bearing according to claim 1, characterized in that each fixing screw (50) is engaged on a flat surface (12 d) from the second ring (12) ₁ ) An axially extending threaded bore (52).

3. Rolling bearing according to claim 1 or 2, characterized in that the flat surface (12 d) of the second ring (12) ₁ ) Extending in a radial direction.

4. Rolling bearing according to any of the preceding claims, wherein said second ring (12) is providedHaving opposite front faces (12c, 12d) defining in the axial direction the axial thickness thereof, said second ring being axially abutted against said flat face (12 d) of said flange (44) ₁ ) Is formed on one of these front surfaces (12c, 12 d).

5. Rolling bearing according to any of the preceding claims, wherein the flange (44) comprises at least one root (56) engaged in a groove (58) of the second ring (12).

6. Rolling bearing according to claim 5, wherein the groove (58) is axially from the flat surface (12 d) of the second ring (12) ₁ ) And (4) extending.

7. Rolling bearing according to any of the preceding claims, wherein said first ring (10) comprises at least one retaining shoulder (60) axially facing at least partially said flange (44) and a fixing screw (50), said retaining shoulder (60) being located axially on the opposite side of said second ring (12) from said row of axial rolling bodies (18).

8. Rolling bearing according to claim 7, wherein the axial clearance (62) provided between the flange (44) and the retaining shoulder (60) is smaller in size than the flat surface (12 d) of each fixing screw (50) in the axial direction with respect to the second ring (12) ₁ ) The length of the protrusion.

9. Rolling bearing according to any of the preceding claims, wherein the first ring (10) comprises at least one support ring (14) and at least one retaining ring (16) axially superimposed with respect to each other, the radial raceway (28) of the first ring (10) being provided on the support ring (14).

10. Rolling bearing according to claim 9 when dependent on claim 8 or 7, wherein said support ring (14) is provided with said retaining shoulder (60).